1// -*- C++ -*-
2
3// Copyright (C) 2005-2022 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library.  This library is free
6// software; you can redistribute it and/or modify it under the terms
7// of the GNU General Public License as published by the Free Software
8// Foundation; either version 3, or (at your option) any later
9// version.
10
11// This library is distributed in the hope that it will be useful, but
12// WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14// General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
23// <http://www.gnu.org/licenses/>.
24
25// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
26
27// Permission to use, copy, modify, sell, and distribute this software
28// is hereby granted without fee, provided that the above copyright
29// notice appears in all copies, and that both that copyright notice
30// and this permission notice appear in supporting documentation. None
31// of the above authors, nor IBM Haifa Research Laboratories, make any
32// representation about the suitability of this software for any
33// purpose. It is provided "as is" without express or implied
34// warranty.
35
36/**
37 * @file priority_queue.hpp
38 * Contains priority_queues.
39 */
40
41#ifndef PB_DS_PRIORITY_QUEUE_HPP
42#define PB_DS_PRIORITY_QUEUE_HPP
43
44#include <bits/c++config.h>
45#include <ext/pb_ds/tag_and_trait.hpp>
46#include <ext/pb_ds/detail/priority_queue_base_dispatch.hpp>
47#include <ext/pb_ds/detail/standard_policies.hpp>
48
49namespace __gnu_pbds
50{
51  /**
52   *  @defgroup heap-based Heap-Based
53   *  @ingroup containers-pbds
54   *
55   *  @{
56   */
57
58  /**
59   *  @defgroup heap-detail Base and Policy Classes
60   *  @ingroup heap-based
61   */
62
63  /**
64   *  A priority queue composed of one specific heap policy.
65   *
66   *  @tparam _Tv 	    	Value type.
67   *  @tparam Cmp_Fn	    	Comparison functor.
68   *  @tparam Tag 	    	Instantiating data structure type,
69   *			    	see container_tag.
70   *  @tparam _Alloc 	    	Allocator type.
71   *
72   *  Base is dispatched at compile time via Tag, from the following
73   *  choices: binary_heap_tag, binomial_heap_tag, pairing_heap_tag,
74   *           rc_binomial_heap_tag, thin_heap_tag
75   *
76   *  Base choices are: detail::binary_heap, detail::binomial_heap,
77   *                    detail::pairing_heap, detail::rc_binomial_heap,
78   *                    detail::thin_heap.
79   */
80   template<typename _Tv,
81	   typename Cmp_Fn = std::less<_Tv>,
82	   typename Tag = pairing_heap_tag,
83	   typename _Alloc = std::allocator<char> >
84  class priority_queue
85  : public detail::container_base_dispatch<_Tv, Cmp_Fn, _Alloc, Tag>::type
86  {
87  public:
88    typedef _Tv 					value_type;
89    typedef Cmp_Fn 					cmp_fn;
90    typedef Tag 					container_category;
91    typedef _Alloc 					allocator_type;
92    typedef typename allocator_type::size_type 		size_type;
93    typedef typename allocator_type::difference_type 	difference_type;
94
95  private:
96    typedef typename detail::container_base_dispatch<_Tv, Cmp_Fn, _Alloc,
97						     Tag>::type
98 							base_type;
99    typedef detail::rebind_traits<_Alloc, _Tv>		__rebind_va;
100
101 public:
102    typedef typename __rebind_va::reference 		reference;
103    typedef typename __rebind_va::const_reference 	const_reference;
104    typedef typename __rebind_va::pointer 	   	pointer;
105    typedef typename __rebind_va::const_pointer 	const_pointer;
106
107    typedef typename base_type::point_iterator 		point_iterator;
108    typedef typename base_type::point_const_iterator 	point_const_iterator;
109    typedef typename base_type::iterator 		iterator;
110    typedef typename base_type::const_iterator 		const_iterator;
111
112    priority_queue() { }
113
114    /// Constructor taking some policy objects. r_cmp_fn will be
115    /// copied by the Cmp_Fn object of the container object.
116    priority_queue(const cmp_fn& r_cmp_fn) : base_type(r_cmp_fn) { }
117
118    /// Constructor taking __iterators to a range of value_types. The
119    /// value_types between first_it and last_it will be inserted into
120    /// the container object.
121    template<typename It>
122    priority_queue(It first_it, It last_it)
123    { base_type::copy_from_range(first_it, last_it); }
124
125    /// Constructor taking __iterators to a range of value_types and
126    /// some policy objects The value_types between first_it and
127    /// last_it will be inserted into the container object. r_cmp_fn
128    /// will be copied by the cmp_fn object of the container object.
129    template<typename It>
130    priority_queue(It first_it, It last_it, const cmp_fn& r_cmp_fn)
131    : base_type(r_cmp_fn)
132    { base_type::copy_from_range(first_it, last_it); }
133
134    priority_queue(const priority_queue& other)
135    : base_type((const base_type& )other) { }
136
137    virtual
138    ~priority_queue() { }
139
140    priority_queue&
141    operator=(const priority_queue& other)
142    {
143      if (this != &other)
144	{
145	  priority_queue tmp(other);
146	  swap(tmp);
147	}
148      return *this;
149    }
150
151    void
152    swap(priority_queue& other)
153    { base_type::swap(other); }
154  };
155 ///@} heap-based
156} // namespace __gnu_pbds
157#endif
158